Kinetics of hydrolysis of sodium borohydride for hydrogen production in fuel cell applications: A review

• Published in: International journal of hydrogen energy Vol. 36; no. 16; pp. 9772 - 9790
• Main Authors: Retnamma, Rajasree, Novais, Augusto Q., Rangel, C.M.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01-08-2011; Elsevier
• Subjects: Alternative fuels. Production and utilization; Applied sciences; Borohydrides; Catalyst; Energy; Exact sciences and technology; Fuel cell; Fuel cells; Fuels; Hydrogen; Hydrogen production; Hydrogen storage; Hydrolysis; Kinetics; Mathematical models; Reaction kinetics; Sodium; Sodium borohydride; Hydrolysis; Kinetics; Sodium borohydride; Hydrogen production; Catalyst; Fuel cell; Hydrogen storage; Hydrogen; Review; Hydroborates; Hydrogen fuel cells; Storage capacity; Aqueous solution; Performance
• ISSN: 0360-3199; 1879-3487
• DOI: 10.1016/j.ijhydene.2011.04.223

Hydrogen generation from the hydrolysis of sodium borohydride (NaBH
4) solution has drawn much attention since early 2000s, due to its high theoretical hydrogen storage capacity (10.8 wt%) and potentially safe operation. However, hydrolysis of NaBH
4 for hydrogen generation is a complex process, which is influenced by factors such as catalyst performance, NaBH
4 concentration, stabilizer concentration, reaction temperature, complex kinetics and excess water requirement. All of these limit the hydrogen storage capacities of NaBH
4, whose practical application, however, has not yet reached a scientific and technical maturity. Despite extensive efforts, the kinetics of NaBH
4 hydrolysis reaction is not fully understood. Therefore, better understanding of the kinetics of hydrolysis reaction and development of a reliable kinetic model is a field of great importance in the study of NaBH
4 based hydrogen generation system. This review summarizes in detail the extensive literature on kinetics of hydrolysis of aqueous NaBH
4 solution.
► State of the art on the kinetics of NaBH
4 hydrolysis. ► Analysis of mechanistic and empirical approaches to modeling of self-, pH-catalyzed and metal- catalyzed NaBH
4 hydrolysis. ► Identification of major factors that influence NaBH
4 hydrolysis kinetics under various ranges of operation. ► Performance comparison and shortcomings of established kinetic models.